/**
 * @license
 * Copyright 2018 Google Inc. All Rights Reserved.
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 * =============================================================================
 */

import * as tf from './index';
import {ALL_ENVS, describeWithFlags} from './jasmine_util';

describeWithFlags('nextFrame', ALL_ENVS, () => {
  it('basic usage', async () => {
    const t0 = tf.util.now();
    await tf.nextFrame();
    const t1 = tf.util.now();
    // tf.util.now should give sufficient accuracy on all supported envs.
    expect(t1 > t0);
  });

  it('does not block timers', async () => {
    let flag = false;
    setTimeout(() => {
      flag = true;
    }, 50);
    const t0 = tf.util.now();
    expect(flag).toBe(false);
    while (tf.util.now() - t0 < 1000 && !flag) {
      await tf.nextFrame();
    }
    expect(flag).toBe(true);
  });
});
